Projeto e análise de redes de antenas de microfita para transmissão de dados meteorológicos em nano-satélites

Abstract

The use of microstrip antennas presently is a viable option for spacecraft applications. However, there are no consolidated antenna models for this type of application. This paper presents the study of microstrip antenna arrays for meteorological nano-satellites that are under development in the frame of Uniespa¸co programme, which is supported by the Brazilian Space Agency (AEB). The main goal of such nano-satellites is to serve as meteorological data relay collected by stations deployed in remote areas, such as in the rain forest, that can be reached only by wireless communication. Arrays composed of linearly and circularly polarized microstrip antennas using electromagnetic coupling feed will be studied. The performance of such arrays is assessed including parameter variations, especially for the case of dielectric constant of the antenna substrate and misalignment in the orientation of the array elements. Such imperfections can occur due to mechanical stress and large temperature variations that are typical to the space environment. The design of the feeding system of four antennas that make up the array will be shown and discussed. The study and design of the complete system including the antenna array together with the feeding system is presented. The antennas were modeled with the electromagnetic simulator Ansys HFSS. Good results have been observed in terms of axial ratio, inputimpedance, reflection coefficient, bandwidth and gain for the proposed models.